I was vegetarian from when I was 13 until when I was 24. And I recently switched back to vegetarian, a few weeks ago.
You have to be careful about how you do it. I gained a lot of weight while eating vegetarian the first time. Like you, my family didn't really know anything about it. This meant I ate what they were eating without the meat- spaghetti with sauce only, etc. When I went out to eat, I would order the "vegetarian option"- grilled cheese and fries. Um, not so healthy. It is very easy to consume a lot of fat and not a lot of protein on a vegetarian diet.
Natural foods other than meat that are high in protein can also be high in fat- nuts, cheese, yogurt. Of course, you can get low fat versions, but I don't... that's a different story. Since I switched my diet this time, I'm still counting calories and I noticed my fat percentage has gone up quite a bit, while my protein has gone down. Not sure it matters... I'm still losing weight just fine.
I like it. Feels good and I feel like I'm doing the best thing for myself, health wise and morally. It's forcing me to eat more variety and completely avoid fast food. Both positive changes.
My blog, This is not a Diet:http://notsobigk.wordpress.com
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